Currently, Linux users can play Windows Media Video (WMV) and Windows Media Audio (WMA) content if they install closed-source modules, said Jeff Duchmann, general manager of client and digital rights management technologies at RealNetworks. As a result of a licensing deal RealNetworks signed with Microsoft and its settlement of an antitrust suit against the software giant, RealNetworks will build the Windows Media support into its proprietary RealPlayer for Linux software, the company said. The support will not be in the open-source Helix Community project it launched to bring some RealNetworks technology to Linux.

However, the software won't support digital rights management available with Windows, he added.

RealNetworks also is evaluating adding support for the AAC compression format, an audio compression format used by Apple Computer's iTunes and others, he said, though that would require further licensing actions for the company. "If we're going to do music services on other platforms, like Linux, we're going to have to support it," he said.

Duchmann added that RealNetworks also hopes to bring its music store technology to Linux.

Expanding application support is a key part of making Linux viable on desktop computers. It's a goal many companies have chased, largely unsuccessfully, for years. Novell is the largest company currently working on the idea, employing a catch-phrase of spreading Linux "from the desktop to the data center."

"We have for the first time a real alternative to the Windows desktop. Linux and open source are there," said at a news conference. In particular, there's a big chance for companies to make their case as customers evaluate Microsoft's new Vista version of Windows.

"Over the next six months, there is an opportunity for the IT organizations to do a significant pilot--to find several hundred users who are knowledge workers and let them as a pilot try out our desktop," Jaffe said.

Correction: Due to incorrect information provided by a RealNetworks representative, this story incorrectly described the company's plans to add Windows Media Video and Audio support to Linux. Such support will be in the proprietary RealPlayer for Linux software.